这个代码为什么不能运行起来

Question

#include<stdio.h>
#include<time.h>
#include<stdlib.h>

void menu()
{
printf("***********************\n");
printf(" 1:play o:exit ********\n");
printf("*****************************\n");
}
void game()
{
int ret = rand() % 100 + 1;
int guess = 0;
while (1)
{
printf("请猜数字:>");
scanf_s("%d", &guess);
if (guess > ret)
{
printf("猜大了");
}
else if (guess < ret)
{
printf("猜小了");
}
else
{
printf("恭喜你，猜对了");
break;
}
}
}

int main()
{
int input = 0;
stand((unsigned int)time(NULL));
do {
menu();
printf("请选择>:");
scanf_s("%d",&input);
switch (input)
{
case 1:
game();
break;
case 0:
printf("退出游戏\n");
break;
default:
printf("选择错误\n");
break;
}
} while (input);
return 0;
}

Answer 1

srand((unsigned int)time(NULL));